Earphone socket



Oct. 1, 1946. s. S. STEVENS EARPHONE SOCKET 2 Sheets-Sfieet 1 Filed April 18, 1944 INVENTOR [fi o/w f- 1946- I s. s. STEVENS I 4 3,

EARPHONE SOCKET Filed'April 18, 1944 2 Sheets-Sheet 2 V 3 7 Fig.4.

IYINVENTOR STANLEY SMITH STEVENS ,f/farrragl.

Patented Oct. 1, 1946 EARPHONE SOCKET Stanley Smith Stevens, Cambridge, Mass., assignor to the United States of America, represented by the Executive Secretary of the Oifice of Scientific Research and Development Application April 18, 1944, Serial No. 531,684

This invention relates to sound control devices and more particularly toan earphone and socket assembly for use with aviation helmets, headsets and the like. 1

A customary practicehas been to mount earphones in an aviation helmet and to utilize chin straps to press the earphonesfirmlyagainst the ears in an effort to exclude ambient noise from passing around the earphone into the ear canal. This arrangement has not been satisfactory. Continuous pressure of the earphones against'the ears'may give rise to considerable discomfort and in addition the earphone is never completely sealed around the outer ear. Intense noise such as is developed in the operation of modern aircraft may enter the ear canal and become painful and may render substantially unintelligible signals received from a radio or interphone.

To surmount these difliculties, it has been proposed to surround the earphone, at the inner side of thehelmet, with a, member which is commonly referred to, in the'art, as a doughnut. This member essentially consists of a sealing member of annular cross section, formed of a relatively soft yieldable material whose function in part is to serve as a spacing member for supporting the earphone immediately adjacent to that ambient noise may'pass betweenithe earphone and the sealing member as well as through the sealing member itself, in either case leaving the ear canal relatively unprotected.

It is an object of the invention therefore to provide an improved sound control device for earphones, and to devise an'earphone support or socket in which are incorporated sound attenuating means directed to overcoming the difficulties above noted, and to providing a combined sound insulating and sealing effect, It is also an object of 'the'invention to provide a simple, cheap and efficient device of the character referred to, which is conveniently attached to an aviation helmet and which avoids interference with the normal use of the helmet.

' The nature of the invention and its objects will be more readil y understood from-the fol I 3 Claims. (Cl.179-156) lowing description of the drawings and discussion relating thereto.

In the accompanying drawings:

Fig. 1 is a view in elevation illustrating the socket of the invention mounted at the inner side of an aviation helmet which has been diagrammatically indicated;

Fig. 2 is a view in side elevation of the socket;

Fig. 3 is a cross sectional view taken on the line 3?-3 of Fig.1;

Fig. 4 is a horizontal cros section diagrammatically illustrating a skull and ear, with the socket of the invention being indicated'in an t operative position at the side of the skull; Fig. 5 is an elevational view of the outerside of the socket; 1 I

Fig. 6 is an elevational view illustrating a modification of socket;

Fig. '7 is a detail view diagrammatically illustrating a skull and indicating the position assumed by the sealing member of the invention as it contacts the side of the skull; and

' the outer ear without compacting the ear against Fig. 8 is a detail view diagrammaticaly illustrating a skull and indicating the position assumed by the sealing member at another point of contact with the skull.

The invention in general provides for a holder or socketin which both an earphone and a sealing member, of the doughnut type, may be mounted. The socket is made of sound insulating material, and designed to extend between the earphone'and the sealing member and to overlie a substantial part of the sealing member itself. The socket is also formed so as to provide for a rearrangement of the sealing member and the earphone, relative to the skull and ear respectively, thereby further increasing the efi'lciency of the earphone and sealing member.

Referring more in detail to the drawings, numeral i denotes a sealin member or doughnut of the type already referred to (Fig. 1). This member consists of a continuous ring of annular cross section which -may,- for example, comprise a casing of chamois, stuffed with a soft yieldable material such as kapok. Sponge rubber and fibrous materials are also used in making the sealing member. By reason of its yieldable char- 1 acter, the sealing member is particularly adapted Numeral 2 refers to an earphone of conventionaltype employed in aviation helmets, andis inner side against which the sealing member I is secured as shown in Fig. l, and an outer side from which the earphone 2 projects, asfimaye-be more readily seen in Fig. 4.

At its inner side, the socketis formed witlra central body portion 6 which is'rlalatively thioker;

than other portions of the socket and which presents a flat surface 3a. Numeral Sden'otes an earphone opening extending'through :"thewbody portion 4. The edge of the opening imay ifdesired be beveled as shown in Fig. 2, to facilitate engagement of the socket with the earphone 2.

' The earphone 2 occurs --in-a somewhat recessed position relative to those peripheral-portions of the sealing member I which are to engage against theiskull. Atpoints betweenthe inner and outer sides 'ofthe' socket 3 and adjacent to the opening 5,-the' body portion 4 has-been formed with-a channel 6, which is adapted' -to'rec'eive a rib I on the outer peripheryof the earphone 2.

The central-body portion'4 occupies the space between the outer periphery of the-earphone 2 and the inner pe'riphery'of the sealing member I; as may be-seen from an inspection of Figs. 1

and 3, and by reason of its thickness, thebody portion-provides a relatively heavy mass of sound insulationwhich is effective in attenuating the passage of sound between the earphone and the sealing member.

The outer peripheral portions-of the socket 3 are curved around the sealing member l *to provide a lip or rim 8"which, at its inner side, conforms to the contour of the sealing member and presents a groove 9 surroundingthe body por- "tion 4. "The groove 9 provides aseating in which the sealing member may be conveniently secured "by the use ofan adhesive material. "By allowing the socket to extend across the overlie the sealing member inthe' manner'described, a second important-sound insulating effect is obtained,

Relative to a plane passing through theflat face 4a Ofthe body portion 4; the groove 9 extends more deeply throughout the front half of the socket than throughoutits rear half. 'The term front half refers to that' portionof the socket-which in use 'occurs substantially in front "of the ear, and correspondingly the term rear A half refers to'the socket portion occurring substantially in back of the' ear. As viewed in*Fi'gs.

'1, 3 and 4,-thesocket' member has its front half occurring at the "left-hand side of the figures. In

addition, the groove 9; with respect to the-refer- "ence'pl'ane not'edfbegins to change in depth as "it-extends around the front half of the socket and gradually :cleepens' until it reachesits greatest depth at a point approximately halfway .around the front half.

-surface throughoutits rear half .as illustrated 4 in Fig. 4.' There is thus provided a thickness of material, directly over the sealing member I, which is substantially uniform throughout both the front half and rear half of the socket.

The rim 8, in relation to the reference plane of the face 4a, also changes in height and as it extends around the front half of the socket grad- ?sua-l-ly decreases-mo a .lowmpoint sicorrefsponding to the point ofgre'atest depth ofthe' groove 9.

The irregularityin depth of the groove 9 pro- "=vides for an offset arrangement of the sealing member I in relation to the reference plane passing through the face 4a. By supporting the sealing member' more deeply throughout the -front-l ialf of'the socket, than throughout the rear half,the-corresponding front half of the earphone'2 is brought substantially nearer to the 1* :conta'cting surface of the sealing member than the rear half of the earphone. When the socket assembly is placed over an ear E, as diagrammatically illustrated in Fig. l, the earphone in relationtoathe skull S-will be spacedaway a greater idistance' atiits rear -ha'lf than' 'at its front half.

.-;An*-iimmediate'result of this asymmetrical arrangement of the earphone with respect' tothe sealingimember is to allow the inner surface of *ithe earphone 2: to be placed in a position in which 1: it closelyiconforms to the natural-angle of pro- 11 jiecti'on'f of the.- outer "ear: and reduces the space between theearphone and'the ear canal.

.JIt is'a'of 'importancein the acoustic performance 'of this device "that the volume of air between the earphone and theiear canal be reduced to a minii'Lmum. JiA relatively small 'volume'of air-between ::Ethe :earphonez'and the ear -canal tendsto render a signalz ireceived' fr'om the earphone 1 more in- --:tense"; since for. the: available sound energy in the .iisign'alithere is less lair to be-activated. The oil'- set relation of the'rearphone with respect :to 'the .sealing:membenaccomplishes a desirable reduc- :::tion in ithe vo'lumerof air. :The offset relation --:further.1allows thevface 'of the earphone to come .intmthenclosest possible contact with the outer :ear;1 while :still: allowing 'Ithe sealing member to maintain 'itsspacing functionso that the outer Y BaI iS rrot'icompa'cted' against the skull," and so that the: discomfort: :consequent upon such com- T. xpaction. is avoided.

The' variation in"- the depth of "groove -9 and 1-heightbf -rim'8furnishes still other beneficial rei-sults by reshaping-the contacting surface of the se'aling member l. As may be more clearly seen r ."in FigI .2, the socketimparts to the contacting .i-JsUrfaceiOf the sealingLmember I throughout its :1fr.ont half; a slight concavity. :When the socket is.-in":use',3this concavity allows the sealing mem- -'ber tooverlieiandi' conform to the raised part of i'zthei'skull. Socourring directly infront of the outer aear at; thec-cheek bone; and provide. an. improved :sealnas is diagrammatically shown. in Fig. '5. At

rthesame; time the :lower partof. the sealing. member, due to:thef:concavity;.-tends..to: :conform to and fill .inithe space: immediately below the outer rrearsatithenmastoidfiprocess,'-as't has been diagrammatically illustrated in Fig; 8.

By:thus.--rearranging 'the;.sha-pe 10f the-sealmg-member; a more: complete; acoustical sealing is Y achieved. at the hollow above the cheek bone and the hollow at=the mastoid process, sothat' with a :1. given; pressure; a --substantially uniform sealing i'fl effectais obtained-all thezway around the skull,

and.'any rpossibler sourceiofisoundi penetration at :these;-points-t-is largely: eliminated. 'It should also be -noted-that the decreased-edgeof the rim 8. at Y. the front. edge .of the: socket r'permits the doughnutsto be morecloselyspressed against the skull in the offset relation described without bear against the skull and cause discomfort.

l0 denotes a protecting lining which may, for:

example, consist of chamois, disposed over the in-; ner side of the socket and is particularly adapted to cover the body portion 4 to prevent this material from coming into direct contact with the outer car. In this connection, it is pointed out thateither from the point of view of protecting the outer ear from contacting a cold rubber sur-' face during low-temperature flying conditions, or from the point of view of toxicity from the con? 'tact of the outer ear with the insulating mate-j rial, the protecting lining is particularly desirable.

The invention also includes a stitching flap ll formed of some suitable material such as a In assembling the earphone assembly in a. helmet, the flap II is stitched at the border of hole cut into the helmet to permit the earphone I Theffl socket member is positioned so as to naturally to project outwardly therefrom (Fig. 1).

surround the outer ear with the front edge ofthe socket occurring substantially vertical. should be noted that the socket may be used either for a left or a rig-ht ear by simply turning it end for end, thus effecting substantial saving in manufacture. In operation, the helmet is adjusted over the head in the usual manner with met are fastened togetherwith a light pressure being exerted on the sealing members, enabling these members to provide a seal against the head at all points around the cars.

In Fig. 6 I have shown a modification of the in-- vention for use with a headband in which the bined sound insulating and sealing effects noted in connection with the description of the socket remove all disadvantages of the earphone and doughnut type of assembly without in any way causing discomfort or interfering with the use of goggles and other equipment over the helmet. The socket is a simple efiicient unitary member capable of being easily and cheaply molded on a quantity basis.

While I have shown a preferred embodiment of the invention, it should be understood that various changes and modifications may be resorted to, in keeping with the spirit of the invention as outlined by the appended claims.

Having thus described the invention, what I claim is:

1. As an article of manufacture a sound control device comprising an earphone, a socket member having the earphone centrally supported therein, a sealing ring of yieldable material mounted in a groove in the inner side of the socket in spaced relation to the earphone, said socket including a relatively thick body portion of sound insulating material occupying the space between the earphone and the sealing ring and adapted to provide sound insulation therein, said socket having outer peripheral portions overlying and extending around the sealing ring to form a rim, the outer peripheral portions of the socket adapted to provide a sound insulating material for the sealing ring, said groove extending more deeply into the socket at the front half thereof than at its rear half to arrange'the sealing ring in offset relation with respect to the earphone, a stitching flap secured to socket adjacent the outside of said rim, said flap adapted to be stitched to the inside of a helmet for the purpose of installing the socket assembly therein.

2. As an article of manufacture a socket for an earphone and sealing ring assembly, said socket consisting of a cup-like member of sound atten-' uating material in which is centrally formed an opening for receiving and supporting an earphone, said socket being formed at its inner side outer side of the socket 3 is formed with slot'slZ and I 3. The slots, l2 and I3 are cut into the" socket to provide a means of engaging the ex tremities of a headband yoke where it maybe desired to use the socket with this type of equipment. The slot I4 is provided to admit electrical connections. It may also be desired to employ the socket with other types of equipment.

The socket may be modified in various ways.

For example, it may be-constructed in two or more pieces and may be formed of two ormore v Various other member for supporting both the earphone and the sealing member. The opening and channelled edge furnish a simple and eflicient means of releasably holding the earphone. The comtion for the sealing member.

3. As an article of manufacture a sound control device comprising an earphone, a socket member having the earphone centrally supported therein, a sealing ring mounted at the inner side of the socket in spaced relation to the earphone, said socket consisting of a cup-like member of insulating material extending across and overlying the sealing ring, said sealing ring being embedded more deeply at one side of the socket than the other.

I STANLEY SMITH STEVENS. 

